Polynitropolycyclic cage molecules are central to the current efforts aimed at energetic materials to meet modern requirements for fuels, propellants and explosives. (Alster, J; Iyer, S; Sandus, O. in "The Chemistry and Physics of Energetic Materials", Bulusu S. ed., Kluwer, "The Netherlands", p. 641.) These systems are particularly attractive because strain energy incorporated in the cage combined with the accumulation of nitro groups tend to bolster energy output, while the molecular compactness produces high density materials favorably increasing the detonation velocity. For a recent review of the chemistry of polynitropolycyclic cage molecules, see Marchand, A. P. "Tetrahedron" 1988, 44,2347. Simultaneously, high crystal density materials are advantageous in volume-limited applications.
As a class of compounds, polynitroadamantanes have been of interest for more than a decade since Sollott and Gilbert first synthesized and demonstrated that the bridgehead-substituted 1,3,5,7-tetranitroadamantane exhibited very low impact sensitivity. Please see Sollott, G. P.; Gilbert, E. E. "J. Org Chem" 1980, 45,5405. Subsequently, several members of this class of compounds have been reported including 2,2-dinitro- and 2,2,6,6-tetranitroadamantane. (Archibald, T. G.; Baum, K. "J. Org Chem", 1988, 53,4645)